Rapid Responses to:

ANALYSIS: Siddharthan Chandran What are the prospects of stem cell therapy for neurology? BMJ 2008; 337: a1934 [Full text]

Rapid Responses: Submit a response to this article

Rapid Responses published:

Stem cells for stroke

Nikola Sprigg, Tim England, Philip Bath   (9 January 2009)

Stem cells for stroke 9 January 2009
Nikola Sprigg, Stroke Fellow University of Nottingham, Tim England, Philip Bath Send response to journal: Re: Stem cells for stroke	Dear Editor, The analysis paper by Chandran(1) reviews the prospects of stem cell therapy for neurology, in particular with reference to Parkinson’s disease, multiple sclerosis and motor neurone disease. The author presents a welcome reminder of the need to manage patients’ expectations against burgeoning interest in this field, despite as yet an absence of clinical evidence of efficacy. However, it is disappointing that stroke was not covered, as the burden of disability after stroke is high and well documented, and there have been a number of clinical studies of stem cell therapy after stroke.(2-4) The article broadly reviews potential mechanisms of stem cell action and focuses on unanswered questions regarding whether stem cells may be involved directly in cell replacement or perhaps more likely by enhancing endogenous repair. Despite this, the article covers only exogenous stem cell transplantation, which is fraught with both technical and ethical difficulties. A more attractive option would be to mobilise endogenous progenitor cells, an approach that has been utilised in stroke(5) and multiple sclerosis.(6) Colony stimulating factors such as erythropoietin (EPO) and granulocyte colony stimulating factor (G-CSF) improve outcome in experimental models of stroke and, although a number of small clinical trials have tested them in stroke, to date there is insufficient evidence to justify use,(7) with several randomised controlled trials ongoing.(8) References: 1.Chandran, S. What are the prospects of stem cell therapy for neurology? BMJ 2008;337a:1934. 2.Kondziolka D, Wechsler L, Goldstein S, Meltzer C, Thulborn KR, Gebel J, et al. Transplantation of cultured human neuronal cells for patients with stroke. Neurology 2000;55:565-569 3.Kondziolka D, Steinberg GK, Wechsler L, Meltzer CC, Elder E, Gebel J, et al. Neurotransplantation for patients with subcortical motor stroke: a phase 2 randomized trial. J Neurosurg 2005;103:38-45 4.Savitz SI, Dinsmore J, Wu J, Henderson GV, Stieg P, Caplan LR. Neurotransplantation of fetal porcine cells in patients with basal ganglia infarcts: a preliminary safety and feasibility study. Cerebrovasc Dis 2005;20:101-107 5.Sprigg, N, Bath PM, Zhao L, Willmot MR, Gray LJ, Walker MF, et al., Granulocyte-colony stimulating factor mobilises bone marrow stem cells in patients with sub-acute ischaemic stroke: the 'Stem cell Trial of recovery EnhanceMent after Stroke' (STEMS) pilot randomised controlled trial. Stroke 2006;37:2979-2983 6.Ehrenreich H, Fischer B, Norra C, Schellenberger F, Stender N, Stiefel M, et al. Exploring recombinant human erythropoietin in chronic progressive multiple sclerosis. Brain 2007;130:2577. 7.Bath PMW and Sprigg N. Colony stimulating factors (including erythropoietin, granulocyte colony stimulating factor and analogues) for stroke. Cochrane Database Syst Rev 2006;(2):CD005207 8.Bath, PMW, et al. Stem cell Trial of recovery EnhanceMent after Stroke 2 (STEMS2). http://www.controlled-trials.com/ISRCTN63336619 Competing interests: The authors are running an independent phase II trial of G-CSF funded by a UK charity, The Medical Research Council. P.B. has acted as a consultant to Axaron (who are developing G-CSF) and Lundbeck (who are developing an EPO analogue).